<template>
  <div>
    <!-- 搜索页面头部 -->
    <div class="search-header">
      <!-- 后退按钮 -->
      <van-icon
        name="arrow-left"
        color="white"
        size="0.48rem"
        class="goback"
        @click="$router.back()"
      />
      <!-- 搜索组件 -->
      <van-search
        v-focus
        v-model="kw"
        placeholder="请输入搜索关键词"
        background="#007BFF"
        shape="round"
        @input="inputFn"
        @search="enterFn"
      />
    </div>
    <!-- 搜索建议列表 -->
    <div class="sugg-list" v-if="kw.length!==0">
      <div
        class="sugg-item"
        v-for="(item,index) in suggestList"
        :key="index"
        v-html="lightFn(item,kw)"
        @click="clickFn(item)"
      ></div>
    </div>
    <!-- 搜索历史 -->
    <div class="search-history" v-else>
      <!-- 标题 -->
      <van-cell title="搜索历史">
        <!-- 使用 right-icon 插槽来自定义右侧图标 -->
        <template #right-icon>
          <van-icon name="delete" class="search-icon" @click="clearFn" />
        </template>
      </van-cell>

      <!-- 历史列表 -->
      <div class="history-list">
        <span
          class="history-item"
          v-for="(item,index) in history"
          :key="index"
          @click="clickFn(item)"
        >{{item}}</span>
      </div>
    </div>
  </div>
</template>

<script>
import { suggestListAPI } from '@/api/index.js'
export default {
  data() {
    return {
      kw: '', // 搜索关键字
      timer: null,
      suggestList: [],
      history: JSON.parse(localStorage.getItem('his')) || [
        'API',
        'java',
        'css',
        '前端',
        '后台接口',
        'python'
      ] // 搜索历史
    }
  },

  methods: {
    async inputFn() {
      clearTimeout(this.timer)
      this.timer = setTimeout(async () => {
        if (this.kw.trim().length === 0) return
        const res = await suggestListAPI({ q: this.kw })
        this.suggestList = res.data.data.options
        console.log(this.kw)
      }, 500)
    },
    // old每一项 ,target输入的值
    lightFn(old, target) {
      // ig全局匹配不区分大小写
      const regExp = new RegExp(target, 'ig')
      // old整个数组,regExp是要替换的值替换match
      return old.replace(regExp, match => {
        return `<span style="color:red">${match}</span>`
      })
    },

    // 输入框回车
    enterFn() {
      this.history.push(this.kw) // 保存搜索关键字
      setTimeout(() => {
        this.$router.push({
          path: `/search/${this.kw}`
        })
      })
      this.history = Array.from(new Set(this.history))
    },
    clickFn(val) {
      this.history.push(val)
      setTimeout(() => {
        this.$router.push({
          path: `/search/${val}`
        })
      })
      this.history = Array.from(new Set(this.history))
    },
    clearFn() {
      this.history = []
    }
  },
  watch: {
    history() {
      localStorage.setItem('his', JSON.stringify(this.history))
    }
  }
}
</script>

<style scoped lang="less">
.search-header {
  height: 46px;
  display: flex;
  align-items: center;
  background-color: #007bff;
  overflow: hidden;
  /*后退按钮*/
  .goback {
    padding-left: 14px;
  }
  /*搜索组件*/
  .van-search {
    flex: 1;
  }
}
/*搜索建议列表样式 */
.sugg-list {
  .sugg-item {
    padding: 0 15px;
    border-bottom: 1px solid #f8f8f8;
    font-size: 14px;
    line-height: 50px;
    // 实现省略号的三行代码
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
  }
}
/**搜索历史 */
.search-icon {
  font-size: 16px;
  line-height: inherit;
}

.history-list {
  padding: 0 10px;
  .history-item {
    display: inline-block;
    font-size: 12px;
    padding: 8px 14px;
    background-color: #efefef;
    margin: 10px 8px 0px 8px;
    border-radius: 10px;
  }
}
</style>
